Nanotechnology is a technology that is very small, or at the nanometer scale, which is the size of atoms and small molecules. The United States' National Nanotechnology Initiative Website defines nanotechnology as "The understanding and control of matter at dimensions roughly 1 to 100 nanometers where unique phenomena enable novel applications."  Wikipedia defines nanotechnology as "Any technology which exploits phenomena and structures that can only occur at the nanometer scale, which is the scale of several atoms and molecules." Nanotechnology can be used to make longer-lasting batteries, boats that repel barnacles, cancer treatments, stain-proof clothing, or even weapons.

The first idea of using nanotechnology in a distinguished way was in There's Plenty of Room at the Bottom, a talk given by a physician, Richard Feynman at an American Physical Society meeting at Caltech on December 29, 1959. Richard Feynman described a way to develop the ability to make individual molecules do what you wanted to. The word nanotechnology was defined by  professor Norio Taniguchi of the Tokyo Science University in a 1974 newspaper. He described it as, "Nano-technology' mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or one molecule." During the 1980s, Dr. Eric Drexler investigated the definition and gave the idea as the current sense.
Now nanotechnology is used for many purposes.  Sandia National Labs produces "Self Assembling Nano Inks" which can be used in normal printers. When the inks dry the assemble into arrays, cavities, q-dots ect. Also a company called nanoink makes a "rapid prototyping" nano structure fabrication machine which picks up atom chains and puts then in a precise manner to make files. Also NASA is developing new way to use nanotechnology to help their space missions. They are trying to make a "thinking" spacecraft.